What is the minimum OpenShift 3.11 cluster configuration needed for a medium or large Cloud Pak for Automation production environment?

What is the minimum OpenShift 3.11 cluster configuration needed for a medium or large Cloud Pak for Automation production environment?
A . 3 master. 2 compute nodes, 2 etcd nodes, 3 infra nodes
B . 1 master, 2 compute nodes, 2 etcd nodes, 2 infra nodes
C . 1 master, 3 compute nodes, 3 etcd nodes, 3 infra nodes
D . 3 master, 3 compute nodes, 3 etcd nodes, 3 infra nodes

Answer: C